Repeat type action for typewriters and like machines



H. S. BRINK June 10, 1952 REPEAT TYPE ACTION FOR TYPEWRITERS AND LIKE MACHINES FiledOct. 19, 1949 HERBERTS 8R/NK ATTORNEY power element.

Patented June 10, 1952 REPEAT TYPE ACTION FOR TYPEWRITERS AND LIKE MACHINES Herbert S. Brink, Olean, N. Y., assignor to Underwood Corporation, New York, N. Y., a corporation of Delaware Application October 19, 1949, Serial No. 122,190

6 Claims. 1

This invention relates to power driven type actions for typewriters and like machines and has reference particularly to such type action systems wherein provision is also made for rapidly successive repeat operations of the type for purposes such as underscoring and typing of a series of asterisks, zeros or other characters.

In the art of power type actions it is generally known to provide key operable mechanism for control of the power operation which, upon a momentary depression of the key, will cause a single operation of the type and, upon a sustained depression of that or a separate key, will render a camming device effective to cause a series of repeat operations of the power means.

In type action systems such as that of the Underwood A11 Electric typewriter, exemplified in the Yaeger patent, No. 2,254,764, the type-bar and. its sub-lever, after receiving the power impulse, act independently of the power-operated means. In such type action systems, the known practice of effecting a repeat operation by causing the actuator to becom re-engaged with the power operator may give unsatisfactory results in that the re-engagement of the actuator may occur at intervals varying somewhat from those of the type-bar operations, with th result that uneven or irregular impressions of the type in an underscore. or other series of character impressions may occur.

Accordingly, a primary object of the present invention is to provide a power driven repeat type action particularly suitable for type actions like that of the Yaeger patent, and wherein the timing of re-engagement of the actuator initiated by key-operated means, is positively controlled by th operation of the type-bar.

In the known art of repeat power type actions, of which the repeat mechanisms shown in the Hokanson patent, No. 1,851,311, and the Schulze patent, No. 1,789,661, are typical, the repeat operation is usually effected by cam mean which causes the actuator, while it is being restored, to become re-engaged with the constantly rotating The engagement of the actuator with the power element is necessarily of short duration, for which reason the power stroke and the restoring movement are also short. The camming device, which must be effective in a minor portion of this short stroke, must therefore be abrupt in its action to re-engage the actuator, from which it follows that accurate and nonvarying timing of the instant of each re-engagement in a series of successive power operations is impractical to obtain.

Accordingly, another object to provide improved power actuator re-engaging means, which obviate the difficulties in the known camming devices, the arrangement and manner of operation of which is such as to afford consistently accurate timing of each power re-engagement of a series at the exact instant required to assure uniform type impressions.

Another object is to provide an improved power-actuated repeat type action in which the key-controlled means for effecting repeat typing is controlled also directly by the type action during its operation, to the end that re-actuation of the power element thereof will be effected in harmony with the restoration of the type action to home position.

More specifically, the invention provides a repeat type action wherein the initial typing operation of a repeat series is effected by key-operable means which render effective a repeatcontrol element, said element being momentarily disabled during the forward and part of the return strokes of the type action, the control element efiecting the second and succeeding type action operations during only the final stage of each return stroke of the type action, to assure accurate timed relation of the power re-engagement with the operation of the type action, which may be directly connected to or partly independent of the power means.

Other objects will be in part obvious and in part particularly pointed out as the following description of a preferred embodiment of the invention proceeds.

In the drawings:

Fig. 1 is a perspective view illustrating one of the power-actuated type actions of the typewriter embodying the invention, the same being shown in its inactive and unoperated condition,

Fig. 2 is a sectional view taken on a plane fore and aft of the typewriter, showing the actuated condition of the type action with the repeat key depressed and held down, and,

Fig. 3 is a fragmentary viewof the mechanism as shown in Fig. 2 but with the actuator element about to re-engage the power operator under control of the repeat-control element of the invention.

Prior power type action system To facilitate a clearer understanding of the improved repeat power type action of the invention, the type action system, operative only for a single type impression for each key operation, will be first described. As will laterbe apparent, certain of the invention is of the elements of the type action and its poweractuating means function in both the single and the repeat typing operations. That portion of the type action system herein shown, for obtaining single type impressions, conforms substantially to the power-actuated type action system shown and described in detail in the Yaeger patent, No. 2,257,764, and therefore a brief description of same herein will suiiice.

The usual type-bar 4, pivoted at in a segment 6, is operated from an inactive position at a typebar rest I to strike a platen 8. For clarity only a single type-bar 4 and its actuating mechanism is shown, it being understood that the type action shown is typical of all of the type actions in the typewriter, as will be clear by reference to the Yaeger patent. A link H! operatively connects the type-bar 4 to a sub-lever ll pivoted at l2 on a cross bar of the typewriter. A spring [3 urges sub-lever l l toward its inactive position at which it rests against a yieldable stop l4 on a transverse bar [5. Intermediate the pivot l2 and the connection of link [0, the sub-lever I I has a rounded portion I6 at which a power-actuated lever I! makes a rolling contact with the sub-lever. Lever i1 is pivoted at IS on the transverse bar l5 and is flexibly connected at l9 to a driving link or power actuator 20. The actuator link 20 is urged upwardly and rearwardly by a spring 22 into its normal or inactive position. The upward position of link 20 is determined by engagement of same with an angle bar 23 and its rearward position is gaged by a shoulder 24 on lever l'l engaging the transverse bar l5. The actuator link 20 pivotally carries a snatch pawl 25 capable of limited pivotal movement thereon as determined by a pin on the pawl engaging edges of a slot 26 in the actuator link. By means later described the actuator 20 is swung downwardly about pivot 19 until the teeth of pawl 25 become engaged by the teeth on a constantly rotating toothed power driver or snatch roll 21 driven by suitable means such as an electric motor to revolve in the direction of the arrow.

Under the driving influence of the snatch roll 21, the pawl 25 swings the limited extent shown in Fig. 2, during which swing the pawl edge 28 coacts with the angle bar 23 to ensure engagement of the pawl teeth with those of the snatch roll and by a leverage action give the actuator link 20 its initial drive. After pawl 25 has rotated its full extent, it moves the actuator link 20 leftwardly its full stroke, thus swinging lever l1 leftward to actuate the sub-lever H from its inactive position shown in phantom in Fig. 2 to the fully actuated position shown in full line. The rolling action of lever l1 against the portion it of the sub-lever imparts a gradually accelerated motion to the sub-lever, as fully described in said Patent No. 2,254,764. The power actuation of link 20 by the coaction of pawl 25 with the snatch roll 21 continues to a point where camming action of the actuator 20 with a throw-off screw 29 raises said link until the teeth of pawl 25 become disengaged from snatch roll 21. At this instant the spring 22 becomes efiective to fully raise the actuator 20 and restore same rearwardly to its inactive position shown in Fig. l, the pawl 25 meanwhile also resuming its inactive position on the actuator.

In power-actuated typewriters of the kind herein shown it is preferable to have the typebar driven only part way by power, the remainder of the type-bar stroke to type-impressing position at the platen being preferably under the momentum of the type-bar. Accordingly, as shown portion 16 out of contact with the lever H, which contact is restored as the type action parts resumo their inactive positions, as shown in Fig. 1. The extent or duration of this power actuation diifers somewhat for the various type actions and may be adjusted to suit particular conditions presented in any of the type actions. Such adjustments for either the individual type actions or collectively for the entire type action system are shown and described in said Yaeger patent, No. 2,254,764.

For operating the power type action for a single type impression, a key lever 30 carrying a hook 3| is provided, the hook being adapted to engage over a lug 32 on the actuator link 20. Key lever 30 is pivoted on a bar 33 and is urged by a spring 34 to it upper inactiveposition. At its forward portion the key lever is guided for vertical movement by the usual comb plate and bottoms on a stop member as shown in Fig. 2. The hook Si is mounted on key lever 30 by a pinand-slot connection 35 and is urged by a spring 35 downwardly against the pin of said connection and forwardly about said pin. The upright position of hook 3| on key lever 38 is determined by an ear 3'! on the hook engaging the rear edge of an upstanding member on said key lever. On depressing the key lever 33 the actuator link 20 will be drawn downwardly, the spring 36 being of adequate strength to counteract the force of spring 22, and the operation of the power-actuating means will occur as above described. Only a single power stroke of the actuator link 2|! will occur, even though the key lever 30 is held depressed, since under this condition lug 32, moving rearwardly as its actuator link 20 is restored, will merely engage the upper, front face of the hook element and cause the hook 3| to yield rearwardly while the actuator 20 becomes fully restored free of the snatch roll. On release of the depressed key lever 30 the action of spring 36 on the hook 3! will cause the latter to hookitself over lug 32 and thus become re-engaged with the actuator link 20 in readiness for the next single operation of the type action.-

The power-operated type action thus far described, except for minor variations which will be readily apparent, is substantially like that shown and described in the aforesaid Yaeger patent, and embodies the complete type action system adapted for making only single type impressions for each key lever operation, whether momentary or sustained.

It may be here noted that the above described momentum-movement of the type-bar 4 and the sub-lever H, being independent of the poweractuating means I1, 20, 25, 21, by virtue of the separation afforded between the lover I! and the sub-lever portion l6, may introduce irregular or otherwise faulty repeat typing when such typing is instituted by the known means. Such means usually comprise an element operative to lower the actuator link 20, and a camming device oooperative therewith so as to cause re-engagement of the actuator pawl 25 with the snatch roll during the restoring movement of link 20. In such repeat mechanisms the actuator link 20 may, for example, be fully restored in readipositions described.

I ,5 fness for a repeat aetuati'on--before the type-=haT 4""fully resumes *its inactive position, for which reason the lever ll of the power actu'ating' means may pick up the typeaction sub-lever"! 1 in vari- "able positions as the latter. In a given-series of repeat operations, these variables in each operation may differ appreciably. The-result is that the =type=bar -4 may be givendifierer it-power impulses forat leastsome =of "the repeat at:- -tio ns, and the intensity of the type impressions of 'theser'ies of like'charaoters*mayvary noticeably.

Improved "repeat power type action The improved repeat type actionwnow to *be described obviates the above-outlined *di-ificu-lties and 'assures substantially-uniform type impres sions resulting from a series-of repeat operations, by providing means lay-which the re=en- .gagement of the @power' link with the snatch roll :21 will be effected in timed relation '01 -harmony with the restoration *of the type-bar 4 to its home position. In other words the invention provides key-controlled means-for eiiectin'g .re-

engagement-of the actuator link with the snatch "roll, said means :being also under control of a portion of the type action so that said re-enrgagement may occur at only a"certain'approximate position ofthe type-action at or near that :in'which the type-bar thereof is fully restored, .as -will hereinafterbe more fully explained.

:As shown more -elearl-y in Fig. 1, the sub-lever H is operatively-connected by a link 39 with a repeat power control element 40 embodying :a lever pivoted at 4] on :anamn 4-2 and having'a 'Jfin'ger 43 adapted under certain wccnditionsxto cooperate with the power link zH-at its rearwardly extending portion 4'4.

By mechanism including the-arm "42, the eontrol element 40 may be moved bodily from an inefiective position shown in Fig. -1-toian operative position shown in Fig. 2 in which isai'd 'ele- -ment :is' adapted to effect re-e'ngagement' of the actuator link '20 with the snatch r011 '21, with the type-bar at or near its rest position. This mechanism includes a shaft 45 on which the arm 42 is rigidly attachedsai'd shaft being journalled at one end in a bracket 46 secured tothe tangle bar 23 and at its ether-end in a side qalate -41 of the typewriter main -frame. its outer end, shaft 45 has an farm 48" secured thereto, and a :link 50 operatively connects said arm to "a bell crank '51 pivoted at 52 Jon side' plate 4-1. -A second link "53 operative'ly connects the bell crank 5| to a repeat 'key lever "54' pivoted at '55 on said side plate. The traino'fmechanism .just described, comprising the'key lever '54 at :one end ofthe train and the 'arm :421a1t thecther *en'd, embodies key-operated means by which the *eontrol ele'ment 40 is moved bo'dily to th'ef two It may be ob'sei'ved' that in the-upper or in'efiective position of contr'ol "element 40, :shown in 1, its fi nger 43 is out of operative relation with the end 44 st 'actu'ator link 20, :and the control element may vibrate incident to each power-actuated stroke of thetype a'ction portion 4, N, H without engaging the power link 20. Therefore any single operation of the type-'action as instituted by the afore described-key lever -may be effected without risk of an unwanted repeat operation.

When the typing of a series of impressions of the same character is desiredthe"repeat key lever 54 is depressed and held down. Through the train -of mechanism "45-'53, -depressing -key lever 54 swings arm 42 downwardly so that the 6 @OhtirQ'i-I lament is bediiy lowered to the *fiectiife on' shown in tlot ahd dash outline' in '2. It'shmi-Id 'be 'noted that 'tlii-Fpbs'i'tibh- "of element 40 corresponds with' theinaetive"-positio'n o f -su'b-lever I I and type-bar' '4 shown in lflre outline; which positions said parts of course are in at the time the-Tepeat'key lever 54 is first operated. "I his-"lowering of the control element 411, bodily, causes-its fing'er 43-to first contact and then actuate theactuatorklink'fl to its downwardpo'sition in which its snatch "pawl 25 is brought into 'operative "engagement the snatch roll '21, "thus effecting the fir'st of the series of power actuations-ofthe type action. "Thus, 'on depressing therpeQit key lever '54 the control element 40 is flowered bodily and thereby initiates the first of a series of repeat type action operations, the repetition of which'continues as long as thei'epeat key lever is held 'down. I

TBy holdin'g the repeat key lever 54 depressed, the control "element 40 is maintained in its ef- *fective position. "However, the control element -is only -'effective while the type-bar -4 is-at or near its inactive or home position'and, inversely, becomes momentarily ineffective as the typebarygets under way initsswing-toward the platen. In other words, as demonstrated inFig.f2,-as the type-bar'4 swings from its position on the typebar rest "by the initial stroke of -the"-power-actuating means, the finger -43 ofthe control ele- "ment 40 "moves out of engagement with the factuator link 20 and thus snow said linkgafter concluding itspower stroke, to become-a least partially restored. 'As the type-ban 'furtherappreaches and then strikes'the platen, thefinger 43 moves "farther away from the actuator link part 44.

"As the type-bar '4 'makes "the *firsttype im- 'pression, same engagesan anvil 56 on thesegment 6 and immediately starts its return stroke assisted bfy'the' spring 13 on sub-lever 11. Meanwhile the linkconnectiont-il causes the control element H) to swing clockwise about its pivot 4| so that-the =finger43 thereof is swung, in timed relation to the restoring stroke of type- 'bar "4, -toward contact with the actuator :link part -44. Since it-is desirable, for the' be'st' mode of-operation, to allow-a maxinruin' periodi'or "a substantially Tull restoration or the "power link 20 after 'itspower stroke, itis preferred to cause the reengagementpfits pawl 25 with the snatch 'roll '2?! "only when the "type-bar 4 in its return-stroke closelyappr'oaches the type-bar rest l. 'The'iloca- Ition of the type-bar 4' indicated at X may .be considered an approximation of this (position, .at which the;finger'-'4'3 has become engaged with and partly actuated link .20, but has .not as yet -actually-caused .re-engagement of pawl 25 with the snatch rolL-see Fig. -3. It willof course beiunderstood that this position of the type-bar flzindicatedrait Xisnotcritical andimay be varied somewhat to'suitthe operating characteristics "ot the pai ticular power-actuatedtyperaction. ..-As -the'type"- bar 4 moves ffremgposition X to its 'rest coiitrdl eiemer itfinger 43, already in engagement with the link part 44, lowerssaid li nk so that its pa'wi zt becomesre-enga red with the Fsn'at'ch roll 21 to effect the second power-actuated operation off the-typeaction. In lthefsame manner an immediately r'successiveiseries of "repeat operations will' be' efiected :as long as the repeat key lever 54 ds h'eld depressed. 'Up'on "release ef said key lever a spring 51 restores the operating train 4554, and the arm 42 swings upwardly and thereby bodily raises the control element 40 to its ineffective position.

The preferred embodiment of the invention herein shown is illustrated as incorporated in the power type action of the Underwood All Electric typewriter exemplified in the aforesaid Yaeger patent. It will be understood, however, that the same is shown for the purposes of illustration and that the invention may be modified and embodied in various other forms and may be applied to other kinds of power type actions without departing from its spirit or the scope of the appended claims. Although the improved repeat type ac-- tion control of the invention has certain advantages in respect to the type action of the Yaeger patent, particularly because of the operation of the type-bar and its sub-lever independently of the power-actuating means, the invention has advantageous application also to power type actions such as those of the aforesaid Hokanson and Schulze patents in which the type-bar and its actuating lever are directly connected to the power-actuating means and afford no independent operation of the type-bar. In such applications, the control of re-engagement of the actuator by means including the control element 40 and its operative connection 39 to the sub-lever and typebar will afford accurate and non-varying timing of each power re-engagement at the exact instant required to assure uniform type impres sions throughout a series of like characters.

What is claimed is:

1. In a typewriter or like machine, the combination with a type-bar, a power driver, and an actuator link operatively connected with said type-bar and adapted to engage said power driver to receive a power impulse; of a normally inefiective repeat control means, key-operable means to render said control means effective to cause engagement of said actuator link with the power driver, and means independent of said actuator link and operable by said type-bar incident to its typing movement to momentarily disable said repeat control means.

2. In a typewriter or like machine, the combination with a type-bar, a power driver, and an actuator operatively connected with said typebar and adapted to engage said power driver to receive a power impulse; of a repeat control element normally in an ineffective position, keyoperable means to move said control element to an effective position in which said element is in coactive relation with and causes engagement of said actuator with .the power driver, and means operable by said type-bar incident to its typing movement to momentarily shift said control element out of coactive relation with said actuator.

3. In a typewriter or' like machine, the combination with a type-bar, an actuating lever therefor, a power driver, and an actuator operatively connected with said actuating lever and adapted to engage said power driver for receiving a power impulse therefrom; of a repeat control element, key-operable means including a member on which said control element is shiftable, the last said means being adapted to move said control element bodily to a position in which said element is in coactive relation with and causes engagement of said actuator with the power driver, and means operable by said actuating lever, in its movement. incident to typing movement by the type-bar, to shift said control element first out of coactive relation with said actuator and then again into said coactive relation to cause re-engagement of said actuator with the power driver.

4. In a typewriter or like machine, the combination with a type-bar, an actuating lever therefor, a power driver, and an actuator operatively connected with said actuating lever and adapted to engage said power driver for receiving a power impulse therefrom; of a repeat control element, key-operable means including a swingable arm on which said control element is pivoted, the last said means being adapted upon swinging said arm to move said control element bodily to a position in which said element is in coactive relation with and causes engagement; of said actuator with the power driver, and means operable by said actuating lever, in its movementincident to typing movement by the type-bar, to vibrate said control element about its pivot first out of coactive relation with said actuator and then again into said coactive relation to cause reengagement of said actuator with the power driver.

5. In a typewriter or like machine, the combinationwith a type-bar, a sub-lever therefor, and power-actuating means including a power driver, an actuator link and a lever connected to said link, said actuator link being adapted to engage the power driver for receiving a power impulse, said link-connected lever contacting said sub-lever for transmitting the power impulse to the type-bar, said type-bar and sublever being capable of typing-stroke movement partly independent of said power-actuating means; of a normally inefiective repeat control means, key-operable means to render said control means efiective to cause engagement of said actuator link with the power driver, and means independent of said actuator link and operable by said sub-lever incident to its typing-stroke movement to momentarily disable said repeat control means.

6. In a typewriter or like machine, the combination with a type-bar, a sub-lever therefor, and power-actuating means including a power driver, an actuator link and a lever connected to said link, said actuator link being adapted to engage the power driver for receiving a power impulse, said link-connected lever contacting said sub-lever for transmitting the power impulse to the type-bar, said type-bar and sublever being capable of typing-stroke movement partly independent of said power-actuating means; of a repeat control element normally in an ineffective position, key-operable means to move said element to an effective position in which said element is in coactive relation with and causes engagement of said actuator link with the power driver, and a link connecting said control element to said sub-lever for shifting said control element, incident to typing and return strokes of the type-bar, first out of coactive relation with said actuator link and then again into said coactive relation to cause re-engagement of said actuator link with the power driver.

HERBERT S. BRINK.

REFERENCES CITED UNITED STATES PATENTS Name Date Wittenmyer Feb. 6, 1940 Number 

